Assess anything from Sparks with caution. He's wedded to the M113 as the epitome of mil tech.

With reference to terrain, as ganulv illustrates, 10%, even if accurate is relative. I doubt that figure is accurate and it's in any event totally immaterial. Terrain is but one item in the METT-TC dictum and that dictum should always be assessed in totality and applied to forces to be committed.

You do not fight terrain, you fight people. There are over 400 cities in or on accessible terrain worldwide that have over a million people; in 2008, roughly half the world population was classified as urban. One can use heavy forces in cities but there's a cost and Light or regular Infantry is better suited. That doesn't even address jungle, the Taiga or Mountains where vehicles can go but are sometimes tactically disadvantageous.

There's a place and use for all and too many wars have proven that "One size fits all" is not a good solution. A parochial approach similar to the one espoused by Sparks and too many others as well as the equally bad 'universalist' approach is unwise.

Or you can use light infantry to their strengths. Dominate areas where vehicles are unsuitable (the mountains inside Afghanistan), conduct persistent, economy-of-effort security operations around rural populations and fight the enemy on his own terms (light, away from predictable routes and in areas he doesn't expect it).

Assuming most light infantry deployments require significant vehicular augmentation anyway, wouldn't it make sense to design most infantry TOEs to reflect this? Perhaps even add drivers and gunners so you don't have to dedicate squads to vehicle security while the rest of the unit dismounts.

In the rare situations where vehicles are unsuitable, deploy without them.

From the first link in my last post,

Quote:

To be able to focus our efforts on the population, the task force had to get its maneuver forces to where the people lived. Unfortunately, for a light infantry unit, nothing was within walking distance. Paktika is 19,101 square kilometers, with over 600 kilometers of border with Pakistan. The "box" at the Joint Readiness Training Center at Fort Polk, Louisiana, the Army's premier light infantry training area, is approximately 800 square kilometers, only about one-sixth of which is used by a light infantry battalion during a rotation. According to the MTOE, the primary maneuver forces in a light infantry battalion, the rifle companies, have no internal transportation assets. The only vehicles it has are assigned to headquarters and headquarters company (HHC) and consists of approximately 40 cargo HMMWVs which are used to transport the battalion headquarters, staff, specialty platoons, and limited supplies across the battlefield. This lack of vehicles presented a significant problem for missions that demanded rifle companies and platoons to move hundreds of miles for weeks at a time. Anticipating this sort of challenge prior to deployment, the battalion reorganized and deployed 27 organic HMMWVs, and once in theater, the task force signed for more vehicles that had become installation equipment from previous rotations. The task force signed for approximately 25 M1114, up-armored, five-person models, most less than three years old with improved engines, suspensions, and drive trains. To supplement these gun trucks, the task force also signed for approximately 65 M998, M1038, and other miscellaneous unarmored cargo models, capable of carrying up to 11 Soldiers, their weapons, and supplies. These vehicles, as well as the 27 from Hawaii, had an average age of 15 years and had no improvements to the major stock components. These cargo versions were modified with Kevlar blankets and sheeting to improve survivability, and units strapped M240B machine guns on tripods to the top of the vehicle's cab to create a makeshift weapons platform. With a hodgepodge collection of tactical vehicles, TF 2-27 became motorized.

While creating a fleet of vehicles for the mission in Paktika and motorizing TF 2-27 worked, it was far from ideal. The cargo HMMWV, which made up well over half of the vehicles used by the maneuver elements in the task force, was never meant to be a tactical troop carrier, and its use as such had a variety of disadvantages. The number of vehicles assigned to each company, between six to eight M1114s and 10-15 cargo variants, required companies and platoons to put an average of 10 Soldiers in a cargo variant, and the limited space in the cargo area made carrying the necessary food, water, parts, and equipment to sustain operations challenging at best. The lack of room in the cargo space made firing weapons or defending the vehicle difficult as well.

Quote:

Another problem with reorganizing as a motorized battalion when TF 2-27 arrived in Paktika was the lack of tactical and technical training and experience with vehicles throughout the task force. Though the battalion was a well-trained infantry unit, there was a significant dearth of experience working as a mounted force. The task force lacked qualified drivers and qualified M2 and Mk19 gunners, and few, if any, had conducted a mounted live-fire exercise. As with most infantry tasks, this lack of experience could have been overcome had the task force had vehicles to train with prior to deployment. Although there are a limited number of vehicles in a light infantry battalion, it was not possible to get every company trained in mounted tactics prior to our departure. Once in Paktika, the tactical learning curve was steep, but the battalion accepted a large amount of risk in the first month, using vehicles that the operators were just not trained to use. The technical learning curve was not as steep, and it had greater longterm effect. Maintenance on any piece of equipment is important to ensure that it works when it is needed. It is especially true with vehicles, and that truth is magnified when those vehicles are operating in the conditions mentioned above. Trained vehicle operators are taught to inspect the vehicle before every use, monitor its condition during operation, and check the vehicle every time it stops. The majority of the Soldiers operating vehicles did not receive formal training on the maintenance required for a HMMWV, and this had a major impact on the vehicles. In the first month, operator errors resulted in vehicles breaking down at an extremely high rate. Simple mistakes such as failing to tighten loose half-shaft bolts before operation and putting the wrong kind of fuel in the engine were common, and these mistakes could have been avoided with proper training prior to deployment. Had the rifle companies spent even one month with their vehicles prior to deployment, many of the problems the task force experienced could have been avoided.

Assess anything from Sparks with caution. He's wedded to the M113 as the epitome of mil tech.

With reference to terrain, as ganulv illustrates, 10%, even if accurate is relative. I doubt that figure is accurate and it's in any event totally immaterial. Terrain is but one item in the METT-TC dictum and that dictum should always be assessed in totality and applied to forces to be committed.

You do not fight terrain, you fight people. There are over 400 cities in or on accessible terrain worldwide that have over a million people; in 2008, roughly half the world population was classified as urban. One can use heavy forces in cities but there's a cost and Light or regular Infantry is better suited. That doesn't even address jungle, the Taiga or Mountains where vehicles can go but are sometimes tactically disadvantageous.

There's a place and use for all and too many wars have proven that "One size fits all" is not a good solution. A parochial approach similar to the one espoused by Sparks and too many others as well as the equally bad 'universalist' approach is unwise.

I probably did not explain things well enough. I think Sparks was trying to make the point that most of the world population is located in areas which are accessible to "Stryker like" infantry (in M113 Gavins I would assume).

So, light and regular infantry are better suited for urban warfare? It seems that after the Thunder Runs and battles of Fallujah 11/04, Mosul, Najaf there were many (not saying here at SWJ) advocating heavy armor in cities - that we had made it work unlike the Russians in Grozny?

Or you can use light infantry to their strengths. Dominate areas where vehicles are unsuitable (the mountains inside Afghanistan), conduct persistent, economy-of-effort security operations around rural populations and fight the enemy on his own terms (light, away from predictable routes and in areas he doesn't expect it).

Most commentators seem to come from the same camp area, and that is one which can be used for light infantry and similar units with ready access to heavier equipment.

Such camps can be useful if well provisioned but austere, and situated for supporting extended operations ‘outside the wire’ and not used merely for brief forays into ‘indian county’.

So, light and regular infantry are better suited for urban warfare? It seems that after the Thunder Runs and battles of Fallujah 11/04, Mosul, Najaf there were many (not saying here at SWJ) advocating heavy armor in cities - that we had made it work unlike the Russians in Grozny?

M E TT-TC (emphasis added / kw). It can work, just as armor can be employed in the jungle -- but in both cases, you better know what you're doing and / or be significantly more competent than your opponent.

We made a terrible mistake -- one which many in the Army warned against -- in basing many things on the flawed learning of 'lessons' from Operation Desert Storm. One hundred casualties in 100 hours is not a war and the only lesson is that it's unlikely to be repeatable...

On the first item you mentioned, "accessible" and effective conduct of combat operations are not always synonymous activities. Rarely are, in fact. Regardless, I still question the figure -- and still contend it's immaterial...

So, light and regular infantry are better suited for urban warfare? It seems that after the Thunder Runs and battles of Fallujah 11/04, Mosul, Najaf there were many (not saying here at SWJ) advocating heavy armor in cities - that we had made it work unlike the Russians in Grozny?

M E TT-TC (emphasis added / kw). It can work, just as armor can be employed in the jungle -- but in both cases, you better know what you're doing and / or be significantly more competent than your opponent.

Am I correct in assuming that the decision to employ armor in Fallujah might have been different had the adversary possessed cutting edge anti-tank weapons?

__________________If you don’t read the newspaper, you are uninformed; if you do read the newspaper, you are misinformed. – Mark Twain (attributed)

The 1st Bn (117th Inf. Regt.) was simply a bunch of foot-sloggers - who did arrive North of Stavelot in trucks; but who infiltrated into the town on foot. So, they were infantry - just infantry (not light, heavy or medium) - and National Guard infantry to boot (as was the rest of the 30th Div.).

The bottom line is that an infantry unit (with some AT and arty support) in an urban environment can clean the clock of an heavy armor unit (with attached mech. inf.) if the latter units are not employed properly.

Clean the clock and scatter the parts. The determinant is the quality of the opponent with respect to training and will (thus the emphasized 'E' -- Enemy). The number of people on each side and the equipment used are secondary though obviously more and better is an improvement over enough and good enough. Fallujah was hard enough with the relatively poor quality of opposition, had they been better, it would've been even more difficult. Lacking that, the cutting edge AT weapons would've made little difference.

The 1st Bn (117th Inf. Regt.) was simply a bunch of foot-sloggers - who did arrive North of Stavelot in trucks; but who infiltrated into the town on foot. So, they were infantry - just infantry (not light, heavy or medium) - and National Guard infantry to boot (as was the rest of the 30th Div.).

<Snip>

Regards

Mike

As a historical aside, my old unit was involved enough in the fighting in that portion of the battle to get a presidential unit citation. I dug around and couldn't find much on my old battalion specificly, but I recall that The Damned Engineers (http://www.amazon.com/damned-enginee...7677659&sr=8-1) discussed the fight for St. Vith and Stavelot quite a bit for those who might be historically inclined.

Would it be possible to have a basic, standardized infantry unit ("light"), and put it on trucks or HMMVVs (making it "mot"), APCs or IFVs (making it "mech" or "heavy"), and helicopters (making it "airborne/air assault"), just as the operations require? Making the mobility component a modular attachment to a standardized infantry building block, say a platoon? Could that work? And going one step further, making it "amphib", and thus taking the same standardized basic infantry unit all across the ground combat environment?

Distiller,

I do believe you just outlined a typical Marine Line Company. you just forgot to ad the extra fireteam per squad.

The 1st Bn (117th Inf. Regt.) was simply a bunch of foot-sloggers - who did arrive North of Stavelot in trucks; but who infiltrated into the town on foot. So, they were infantry - just infantry (not light, heavy or medium) - and National Guard infantry to boot (as was the rest of the 30th Div.).

The bottom line is that an infantry unit (with some AT and arty support) in an urban environment can clean the clock of an heavy armor unit (with attached mech. inf.) if the latter units are not employed properly.

Regards

Mike

The standpoint form the German opponent seems that a part of it's dispersed armored and mechanized forces operated in a very unfriendly tank country with a lot of blown bridges with increasing limited supplies in fuel and spares under an umbrella of enemy air supremacy interrupted by bad (good) weather against fresh light infantry supported by far superior artillery firepower and a good amount of AT support holding an urban patch called Stavelot in which the heavy tanks barely could move. So while the mission was to striker further west it had to be changed to secure the supply line, part of miscalculation which touched pretty much every aspect of the METT-TC. Then again the person in charge was chosen by a person in charge equally known for it's military wisdom for it's political reliability...

So while in general it doesn't show the superiority of light infantry in such a setting as much as it shows the influence of factors like leadership, troop quality, terrain, the goal of the mission and the overall supporting ressources of both sides.

Like Israel in 2006, the United States today is likely ill prepared for hybrid warfare after years of focusing on irregular adversaries. To identify lessons that the U.S. military might learn from the Israeli experience in Lebanon, the author examines the following: the state of the Israeli military before the Second Lebanon War, the challenges that Hezbollah's hybrid warfare posed, the lessons the Israelis learned from the 2006 war, the reforms the Israeli military undertook to address its deficiencies, and how Israel fared during Operation Cast Lead three years later.

The author finds that, in facing hybrid opponents, joint combined-arms fire and maneuver are necessary; precision, stand-off fires are critical (but not sufficient); and responsive and adequate air, artillery, and intelligence, surveillance, and reconnaissance support are vital. Finally, heavy forces — based on tanks and infantry fighting vehicles — are key to fighting sophisticated hybrid opponents because they reduce operational risk and minimize friendly casualties.

I wrote a long text and then ditched it. The short form is that I am sure that a division of infantry is justified.

One branch of infantry should be a mix of light infantry, snipers, LRRP and scouts. It would receive area missions and play its role with low force densities.

Another branch should be armoured infantry (on wheeled APC/MRAP, tracked APC, HAPC, IFV or if necessary trucks) and be coined in its mindset, tactics and training by being a combined arms component and close security element of heavy battlegroups. This would be a part of the Schwerpunkt force.

Finally, a third branch should be optimised for easy (time and money budgets, KISS equipment) training and moderate requirements (fitness). This would be the voluntary reserve (national guard, militia, territorial army - whatever) component that adds much quantity and can be assigned infantry-heavy tasks such as occupying or capturing objectives in infantry-friendly terrain with support (for example by armoured recce, non-organic arty).
It would achieve relatively high force densities.
This personnel could also be tasked with lots of auxiliary jobs, such as guarding POWs or helping construction engineers.

The training requirements vary a lot for this, and unifying it into a single infantry force would cost a lot, fall short of desirable quantities (and thus be weak in terms of deterrence) and would leave only a small share of recruits eligible (a problem, since infantry is usually losing against other branches in the competition for the best recruits anyway). It's telling that the SWC's most vocal proponent of a unified infantry comes from the UK, a county with a history of a usually small and relatively highly trained army.

@kaur:
What RAND described are the needs against a conventional opponent with a very limited repertoire - and the "vital" requirements can be met to good satisfaction only in fair weather conflicts (facing an inferior opponent who by this nature is most likely defending his country, not invading yours or one of your allies').

from Firn
The standpoint form the German opponent seems that a part of it's dispersed armored and mechanized forces operated in a very unfriendly tank country with a lot of blown bridges with increasing limited supplies in fuel and spares under an umbrella of enemy air supremacy interrupted by bad (good) weather against fresh light infantry supported by far superior artillery firepower and a good amount of AT support holding an urban patch called Stavelot in which the heavy tanks barely could move. So while the mission was to striker further west it had to be changed to secure the supply line, part of miscalculation which touched pretty much every aspect of the METT-TC. Then again the person in charge was chosen by a person in charge equally known for it's military wisdom for it's political reliability...

So while in general it doesn't show the superiority of light infantry in such a setting as much as it shows the influence of factors like leadership, troop quality, terrain, the goal of the mission and the overall supporting ressources of both sides.

Esp. "leadership, troop quality" - Stavelot was the second time 1 SS Pz had run into 1/117. The first was at St.-Bart near Mortain in Aug 1944. There, the Panzers and their Grenadiers were also stacked up, but it was a close call. See here and here.

As to "overall supporting resources", those were also present at Stavelot - perhaps more good circumstance (luck) than exact operational planning. 1/117 (organically, 3 rifle coys, a heavy weapons coy - MGs & 81mm mortars, an HHC with a pioneer platoon and an AT platoon) had an attached AT Coy (towed) since Aug 1944 (with them at Mortain). That coy had been pulled back to its Bn (along with its other coys) for refitting and retraining with M-10 SPs. It just got back with 1/117 in time for the Stavelot infiltration.

In addition, 1/117 had attached combat engineers (also with them at Mortain), who eventually managed to blow the Stavelot bridge. Further close support were the 117th's regimental mortars and arty. They happened to be plunked down in close proximity to Stavelot - good logistics or luck.

Thus, the US force at Stavelot was de facto a "combined arms task force" - even though not formally designated as such. I've never claimed, BTW, that infantry alone is superior to armor:

Quote:

my BLUF (from my post above - with now added bolding)
The bottom line is that an infantry unit (with some AT and arty support) in an urban environment can clean the clock of an heavy armor unit (with attached mech. inf.) if the latter units are not employed properly.

The Germans did not co-ordinate their panzers and grenadiers. There were good reasons for that (as you've pointed to in the SS 501 articles). Of course, even if they had and eventually wiped out 1/117 and its attached units, that would have taken too long. The Germans were FUBAR because of the "M" and last "T" in METT-T (again as you pointed out).

Esp. "leadership, troop quality" - Stavelot was the second time 1 SS Pz had run into 1/117. The first was at St.-Bart near Mortain in Aug 1944. There, the Panzers and their Grenadiers were also stacked up, but it was a close call. See here and here.

As to "overall supporting resources", those were also present at Stavelot - perhaps more good circumstance (luck) than exact operational planning. 1/117 (organically, 3 rifle coys, a heavy weapons coy - MGs & 81mm mortars, an HHC with a pioneer platoon and an AT platoon) had an attached AT Coy (towed) since Aug 1944 (with them at Mortain). That coy had been pulled back to its Bn (along with its other coys) for refitting and retraining with M-10 SPs. It just got back with 1/117 in time for the Stavelot infiltration.

In addition, 1/117 had attached combat engineers (also with them at Mortain), who eventually managed to blow the Stavelot bridge. Further close support were the 117th's regimental mortars and arty. They happened to be plunked down in close proximity to Stavelot - good logistics or luck.

Thus, the US force at Stavelot was de facto a "combined arms task force" - even though not formally designated as such. I've never claimed, BTW, that infantry alone is superior to armor:

The Germans did not co-ordinate their panzers and grenadiers. There were good reasons for that (as you've pointed to in the SS 501 articles). Of course, even if they had and eventually wiped out 1/117 and its attached units, that would have taken too long. The Germans were FUBAR because of the "M" and last "T" in METT-T (again as you pointed out).

Regards

Mike

Thanks for this very good post. My aim was to point out the implications of the bigger picture and you did a better job then me at that. I might add that they were also FUBAR because of the ET and locally of the second T as well in those circumstances.

In any case it once again shows the importance of quality of leadership at all the levels of a unit. The ability to act and react quickly in times of crisis, taking the initiative is one of the greatest attributes persons and units can have in times of deep and sudden crisis.

After several days of fighting by daring but lightly armed opposition forces, the army, equipped with tanks and heavy weaponry, was forced to pull back on January 18th. Residents hailed their “liberated city” and hung pictures of the dead in a tree. They waved placards and shouted slogans ridiculing the regime. Civilians guarded checkpoints usually manned by the security forces.

it gets down to "the importance of quality of leadership at all the levels of a unit."

Bob Frankland, a National Guardsman from East Tennessee, commanded Curlew (1/117). While decorations are far from an absolute measurement of the man, we find for him: Distinguished Service Cross, Silver Star (w/ Oak Leaf Cluster), Bronze Star (w/ 3 Oak Leaf Clusters). He led from the rear - and from the front ! - and retired in grade of Major General:

Leadership goes beyond officers. Charlie Coy (Co C) was Curlew's tip of the spear for the Siegfried Breakthrough (map here). When the going got rough for Charlie, a PFC from West Virginia, Frank C. Brakefield, got going. First individually and then (after proving it could be done) led a composite squad which he formed - thereby giving heart to the remainder of the company to move forward. As Curlew History notes: "In this situation, a First Platoon man performed in an exceptionally heroic manner." Awarded the Silver Star and promoted to Sgt., Brakefield was available to lead at Stavelot (WIA, 24 Dec 1944).

As important as leadership and individual heroics is training. The 117th Inf. Regt. was the demonstration regiment at the Ft. Benning Infantry School for five months. Curlew (1/117) was the demonstration Bn for the problem "Battalion in a River Crossing". This "make believe" training resulted in a "belief made" attitude which carried over in Curlew.

This study is a General Staff analysis and record of the most important operational details of the XIX Corps’ successful attack on and penetration through the Siegfried Line. This successful attack against the Siegfried Line should be treated largely as a tribute to the superb fighting ability of our infantry and armored soldiers, well supported by artillery and engineers, intelligently led in a well-planned action. It has demonstrated that thorough planning, determined leadership and aggressiveness in battle, can overcome what otherwise seems to be insuperable obstacles. Both, the 30th Infantry Division and 2d Armored Division were battle experienced with able leadership throughout their echelons. The 29th Infantry Division, which came in during the latter phases of the operation, was also a battle experienced Division.
...
(d). Training and Preparation

The assault on the Siegfried Line by the 30th Infantry Division was preceded by intense training all the way down to squad tactics. Despite the fact that units were in the line during this period of training, a reshuffling of reserves enabled all battalions of the 117th Infantry, 119th Infantry and 3d Bn of the 120th Infantry to withdraw behind the lines for reviewing assault tactics. All three battalions of the 117th and 119th Infantry Regiments went through a two day training period in training areas west of the line which they had been holding. The 3d Bn of the 120th Infantry spent most of its time in assault training while in Division reserve. The first and second Bns of the 120th Infantry rotated companies in assault training areas.

The work covered the use of demolitions, flame throwers, bazookas; tactical review of the coordination of assault detachments; practice firing of all weapons; and dry runs in storming the pillboxes and crossing the Wurm River. Engineers, Tank and TD units also rehearsed for the attack, the engineers constructing bridges with the tanks and TDs crossing and fanning out to support the infantry. The practice river-crossing was done in a gully with stagnant water about the width of the Wurm and with the same steep banks. Improvised foot bridges were constructed, two feet wide and 15-30 feet long, with ridged cleats to aid the footing.

Lt Col Robert E. Frankland, battalion commander of the 1st battalion of the 117th, says that “training for the river crossing paid off, because the enemy was surprised and overwhelmed by the sheer aggressiveness of our crossing”.

Under Col Frankland’s direction, an elaborate sand table was constructed, showing in detail the location of the pillboxes, river, wire, roads, ridges, draws, houses and trees. As each reconnaissance patrol returned, changes were made on the sand table to conform with what it had observed. Company commanders were assigned their areas; platoon leaders were shown which pillboxes they were to reduce; squad leaders were drilled in their mission, and before the training had been completed, every man in the assault companies of the battalion was shown the sand table and had his exact route thereon explained to him. Not only the riflemen, but the heavy weapons men, the engineers, the tank destroyer and tank commanders, all studied what was to be their role.

The training was so thorough that, according to S/Sgt Howard King of A Co, 117th Inf Regt, “even when we got a new pillbox to take we just pushed out our support and assault detachment mechanically. The men were also well prepared psychologically. They were inculcated with the necessity for high speed in advancing to the river, crossing, and attacking the fortification. Many men testify that they remembered this when they attacked on October 2, and double-timed through heavy artillery and mortar fire.

BTW: To the extent that I make any sense in the military area is due to following Ken White. My sins here are totally my own.

Regards

Mike

A better and more complete version of the staff report on Siegfried (including links to its nine appendices; last 4 not completed) is here !

Rex Brynen on the Platoon Weapons Thread made the eminently sensible observation that when we are looking at Squad, Section, and Platoon roles, weapons, and compositions, we should be considering the larger tactical circumstances in which they are operating. Here are Rex's proposals:

A couple of questions...
________________________________________
... occur to me as I follow this thread (avidly, I must say, for a non-infantryman).

First, what thoughts do people have on what support weapons should be grouped at the platoon level, what should be grouped at company, and what should be grouped at both (or at battalion)? There has been some discussion of this in passing both here and in the thread on squads/sections, but I've yet to see anyone fully articulate a logic for how one would best decide this.

Second, can we really have a discussion of platoon weapons without more fully discussing APC/IFV issues? Here, I'm less interested in the perennial tracked vs wheeled and heavy versus light issues, and more on the optimal APC/IFV armament. Are 0.50 MGs enough? Should they mount 25/30mm cannon for punching through cover and providing some capability against light AFVs? What about ATGM mounts? (Of course, this also relates to light vs heavy, but let's try to leave that aside for now.)

That was a good question about APC/AIFV armament. Particularly for people like me who believe that all infantry in an industrialised army should be supported wherever practicable by vehicles – preferably armoured vehicles – for all combat and CS tasks and roles. The question was partly addressed in following posts on the Infantry Unit Tactics, Tasks, Weapons, and Organization thread. But the content of those posts was limited because it’s awkward to discuss vehicle armament without also considering vehicle weight. Approximate weight actually makes a good starting point. So here is an abbreviated extract from an unused study of modern armour.

Armoured vehicles are commonly referred to as light, medium, heavy to indicate their combat loaded weight. Historically those same terms have been confusingly used to
secondly describe the calibre of a main armament and thirdly the nature of armour protection. However, the specific calibre of a gun in millimetres has become increasingly used as a descriptor. Similarly, homogeneous or layered protection is now often described in terms of the actual or equivalent thickness in millimetres of rolled steel plate opposing kinetic and chemical attack respectively.

Below for example are the STANAG 4569 protection levels for steel armouring of logistic and light armoured vehicles against KE, artillery and blast threats. With steel at 7,850kg /cb-m, protecting Level 2 ballistic and artillery threats at 105kg/sq-m would require an armour thickness of about 13mm. And to protect a vehicle of M-113 size to Level 2 requires about three tonnes of homogeneous steel, or some equivalent armour.

To conserve weight and reduce corrosion the M-113A1 was built with aluminium alloy armour that has a density of about 2750 kg/cu-m. The thickness of that armour was approx 40mm which provided almost the same degree of ballistic protection as would 13 mm of steel. However the increased thickness and stiffness of the aluminium plate meant that it was largely self-supporting and hence the hull needed few structural beams and ribs. The overall result was much lower vehicle weight than an M-113 built with steel armour.

During the 1960s aluminium armour became less popular because it tends to tear when subject to mine blast and also melts at a lower temperature than steel. Upgraded versions of the M-113 carry a steel belly plate and many have an outer skin of flat or corrugated aluminium or steel. Vehicle weight of the M-113A2 increased from 12 to about 15 tonnes in the M-113A3. The extended M-113A4/MTVL (Mobile Tactical Vehicle Light) with an extra wheel station and more powerful engine has a maximum all-up weight of about 18 tonnes.

Despite the formalisation of ballistic, shrapnel and mine blast threats there are still no commonly agreed meanings or boundaries for light (weight) as opposed to medium (weight) or heavy (weight) armoured vehicles. In some contexts the term light is used to mean vehicles weighing up to about 7 tonnes but in others the term is applied to vehicles such as the M-113 that weigh twice as much and more. So vehicle weight or mass is often discussed using relative terms without boundaries or a clearly understood specification.

The use of weight descriptors with agreed meanings is important because the all-up-weight of an armoured vehicle is a major factor in determining its primary attributes of armament, mobility and protection. Also weight highlights – again indirectly – some of the capabilities and vulnerabilities of armoured vehicles and units. Additionally it makes it easier to assess an armoured vehicle in one weight category against a generally similar vehicle in another category.

Various categorisations of weight can be devised using arbitrary or incremental limits but each is artificial and can become complex as in Table 1. And any such rigorous system of categories is likely to be acceptable only to pedants or Queensbury-style enthusiasts.